I think that the drawings supplied or based on illustrations provided by Olympus are misleading.
Further, basically incorrect in my opinion.
Andrew Davidhazy, School of Photographic Arts and Sciences/RIT
andpph@xxxxxxx http://www.rit.edu/~andpph
Why? Unless that's too complicated for the forum (and me in particular!)
It seems surprising that Olympus would deliberately supply misleading diagrams - or else they don't understand their own technology!
Howard